Currently, a multilayer substrate having at least two circuit layers is usually disposed with conductive vias for the circuit layers to be electrically connected with each other. Taking a circuit substrate disposed with conductive vias as an example, a conventional design manner may cause an issue of impedance mismatching. Specifically, as illustrated in FIG. 1, a conventional circuit substrate 50 disposed with conductive vias is provided, where a distance between an inner conductive via 52 and an outer conductive via 54 may be designed to be an adaptive value for impedance matching, and a distance between a signal circuit 56 and a grounding layer 58 may be designed to be an adaptive value for impedance matching. However, a corner portion 50a is provided at a junction of the inner conductive via 52 and the signal circuit 56, and a corner portion 50b is provided at a junction of the outer conductive via 54 and the grounding layer 58. In a condition where only the impedance matching between the inner conductive via 52 and the outer conductive via 54 and the impedance matching between the signal circuit 56 and the grounding layer 58 are considered, the phenomenon of impedance mismatching still exists between the corner portion 50a and the corner portion 50b. 